Direct methane conversion into aromatic hydrocarbons over catalysts with molybdenum (Mo) nanostructures supported on shape-selective zeolites is a promising technology for natural gas liquefaction. We determined the identity and anchoring sites of the initial Mo structures in such catalysts as isolated oxide species with a single Mo atom on aluminum sites in the zeolite framework and on silicon sites on the zeolite external surface. During the reaction, the initial isolated Mo oxide species agglomerate and convert into carbided Mo nanoparticles. This process is reversible, and the initial isolated Mo oxide species can be restored by a treatment with gas-phase oxygen. Furthermore, the distribution of the Mo nanostructures can be controlled and catalytic performance can be fully restored, even enhanced, by adjusting the oxygen treatment.
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http://dx.doi.org/10.1126/science.aaa7048 | DOI Listing |
J Org Chem
January 2025
Department of Chemistry, Gettysburg College, Gettysburg, Pennsylvania 17325, United States.
Oppenauer-type oxidations are catalyzed by air- and moisture-stable, sustainable, (cyclopentadienone)iron carbonyl compounds, but the substrate scope is limited due to the low reduction potential of acetone, which is the most commonly used hydrogen acceptor. We discovered that furfural, an aldehyde derived from cellulosic biomass, is an effective hydrogen acceptor with this class of catalysts. In general, reactions using furfural as the hydrogen acceptor led to higher isolated yields of ketones and aldehydes compared to those using acetone.
View Article and Find Full Text PDFUnlabelled: One of the principles of prevention and non-drug treatment of liver diseases, including hepatitis of various etiologies, is the normalization of the diet, including the use of daily diet foods with physiologically active ingredients, in particular betulin, which helps to reduce metabolic and oxidative processes within liver cells. The aim of the work was to evaluate the in vivo effect of triterpene alcohol betulin Roth isolated from the bark of birch Betula pendula Roth. added to fat-containing products (for example, mayonnaise) on the biochemical parameters of blood and the morphological structure of the liver of rats with initiated acute toxic hepatitis.
View Article and Find Full Text PDFDiscov Nano
January 2025
Department of Biotechnology, Alagappa University, Karaikudi, 630003, India.
Diabetic wounds with chronic infections present a significant challenge, exacerbated by the growing issue of antimicrobial resistance, which often leads to delayed healing and increased morbidity. This study introduces a novel silver-zinc oxide-eugenol (Ag+ZnO+EU) nanocomposite, specifically designed to enhance antimicrobial activity and promote wound healing. The nanocomposite was thoroughly characterized using advanced analytical techniques, confirming its nanoscale structure, stability and chemical composition.
View Article and Find Full Text PDFNat Prod Res
January 2025
School of Biological Science and Technology, University of Jinan, Jinan, China.
Five previously unreported 5-hydroxymethylfurfural (5-HMF) derivatives, including chinenfurfurals A () and B () as 5-HMF-citric acid hybrids and chinenfurfurals C-E (-) as 5-HMF oligomers, as well as four known analogues (-), were isolated from the fruits of a well-known Chinese herbal species . The structures of these furfural compounds were established by detailed analyses of spectroscopic data especially HRMS and NMR, and it is the first report of furfural type constituents from the title species. The anti-inflammatory property of them was further evaluated by testing their inhibition against the production of nitric oxide in lipopolysaccharide-activated murine RAW264.
View Article and Find Full Text PDFJ Bacteriol
January 2025
Department of Medicine, Division of Gastroenterology and Hepatology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA.
infection (CDI), characterized by colitis and diarrhea, afflicts approximately half a million people in the USA every year, burdening both individuals and the healthcare system. 630Δ is an erythromycin-sensitive variant of the clinical isolate 630 and is commonly used in the research community due to its genetic tractability. 630Δ possesses a point mutation in , an autoregulated transcriptional repressor that regulates oxidative stress resistance genes.
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